Lost buildings and structures

one of the seven wonders of ancient world

unmarked secret burial place in Mongolia

Maymūn-Diz () was a major fortress of the Nizari Ismailis of the Alamut Period described in historical records. It has been variously identified with the Alamut Castle, Navizar Shah Castle, Shirkuh Castle, Shahrak Castle, and Shams Kalayeh Cave. Recently, Enayatollah Majidi located it on top of Mount Shatan ( Kūh-e Shātān; ) near Khoshk Chal.

Roman temple in Cádiz

still unidentified ancient Egyptian pyramid

undiscovered burial crypt of Mark Antony and Cleopatra VII